

declare module Microsoft.Office.WebExtension {

    /** Provides a collection of item-specific custom properties. */
    export class CustomProperties {

        /** Returns the value of the specified custom property. */
        get(name: string): string;

        /** Removes the specified property from the custom property collection. */
        remove(name: string);

        /** Saves item-specific custom properties to the Exchange Server 2013. */
        saveAsync(callback?: any, userContext?: any);

        /** Sets the specified property to the specified value. */
        set(name: string, value: string);
    }
}